With the development of the technology of payment with a mobile terminal, presently, a smart terminal integrated with near field communication (NFC) payment function is becoming a trend. More and more terminal manufacturers support NFC payment, and how to ensure the security of NFC payment has become an important concern. In the related art, when conducting NFC payment, once a smart terminal detects a point-of-sale (POS) machine, the terminal can cause a bank card bound to the NFC function to be in an available state. After the user enters a password of the bank card, the POS machine can be used to read information of the bank card to complete the payment. This method has a security risk in that if the user loses his smart terminal and leaks his payment password, it may cause financial loss. This example of bank card payment shows that the NFC function may have a low security level in information transmission, such as in an NFC payment between a POS machine and a mobile terminal.